Storage Redundancy (1 / 16): Which of the following statements are true about Azure Storage redundancy options: LRS, ZRS, GRS, GRS-RA, GZRS, GZRS-RA? Select all that apply.
Answer:
- Locally redundant storage (LRS): LRS replicates data within a single data center in the primary region. It does not replicate across multiple data centers, so it is incorrect to say that all redundancy options replicate data within the primary region.
- Zone-redundant storage (ZRS): ZRS copies data synchronously across multiple data centers within the primary region. If one of the data centers is temporarily offline, ZRS will not skip it; instead, it ensures that all writes are committed to the durable storage within the zone before being acknowledged to the client.
- Geo-redundant storage (GRS): GRS copies your data asynchronously to a secondary region, making it correct to say that GRS is not always up to date with the primary region. However, GRS does not provide read access to your data from the secondary region, so it's incorrect to say GRS-RA allows read and write operations from the secondary region.
- Read-access geo-redundant storage (GRS-RA): GRS-RA extends GRS by providing read access to the data in the secondary region. It doesn't, however, allow write operations from the secondary region, contrary to the false statement.
- Geo-zone-redundant storage (GZRS): GZRS combines the features of GRS and ZRS. It replicates data asynchronously to a secondary region (like GRS) and synchronously across three Azure availability zones in the primary region (like ZRS). However, it does not replicate data across availability zones in the secondary region, nor does it guarantee data availability during failover.
- Read-access geo-zone-redundant storage (GZRS-RA): GZRS-RA is the read-access variant of GZRS. It provides the same functionality as GZRS, with the added benefit of read access from the secondary region.
Finally, both GRS and GZRS use LRS in the secondary region for data storage, and changing redundancy options could potentially lead to increased cost or affect data durability but it doesn't directly cause data loss.